A novel coral-shaped Dy2O3 gas sensor for high sensitivity NH3 detection at room temperature

作者:Dong, Xin; Cheng, Xiaoli; Zhang, Xianfa; Sui, Lili; Xu, Yingming*; Gao, Shan; Zhao, Hui; Huo, Lihua*
来源:Sensors and Actuators B: Chemical , 2018, 255: 1308-1315.
DOI:10.1016/j.snb.2017.08.117

摘要

The coral-shaped Dy2O3 was prepared by a simple and environmentally friendly hydrothermal reaction combined with subsequent calcination. The coral-shaped Dy2O3 was assembled by clusters, which were constructed by nanoparticles, whose sizes are 12.3 +/- 3.6 nm. The gas sensors were investigated with nine gases at room temperature, and show a high response and selectivity to NH3. Compared with other reported metal oxide-based sensors, Dy2O3 sensor exhibits not only high sensitivity, good selectivity and reproducibility to NH3 at room temperature, but also two good linear relationships when the concentration of NH3 is in the range of 0.1-1 ppm and 1-100 ppm. The good gas sensing property is mainly because of the 3D hierarchical structure of coral-like Dy2O3, which has a large specific surface area. This benefits NH3 molecules to adsorb/desorb onto/from the surface as well as the electron transfer. In addition, the possible NH3-sensing mechanism is discussed in detail.